EP2390948A2 - Aktives elektrodenmaterial für anionenarme lithiumübergangsmetallphosphatverbindung, herstellungsverfahren dafür und elektrochemische vorrichtung damit - Google Patents

Aktives elektrodenmaterial für anionenarme lithiumübergangsmetallphosphatverbindung, herstellungsverfahren dafür und elektrochemische vorrichtung damit Download PDF

Info

Publication number
EP2390948A2
EP2390948A2 EP10733657A EP10733657A EP2390948A2 EP 2390948 A2 EP2390948 A2 EP 2390948A2 EP 10733657 A EP10733657 A EP 10733657A EP 10733657 A EP10733657 A EP 10733657A EP 2390948 A2 EP2390948 A2 EP 2390948A2
Authority
EP
European Patent Office
Prior art keywords
anion
lithium transition
metal phosphate
lithium
mol
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP10733657A
Other languages
English (en)
French (fr)
Inventor
Kyu Ho Song
Soo Yeong Han
Ho Seong Nam
Eui Yong Bang
Se Jin Oh
In Jae Baek
So Yeon Kim
Kyoo Seung Han
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hanwha Chemical Corp
Original Assignee
Hanwha Chemical Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hanwha Chemical Corp filed Critical Hanwha Chemical Corp
Publication of EP2390948A2 publication Critical patent/EP2390948A2/de
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B25/00—Phosphorus; Compounds thereof
    • C01B25/16—Oxyacids of phosphorus; Salts thereof
    • C01B25/26—Phosphates
    • C01B25/45—Phosphates containing plural metal, or metal and ammonium
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/447—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on phosphates, e.g. hydroxyapatite
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/62605—Treating the starting powders individually or as mixtures
    • C04B35/62695—Granulation or pelletising
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/10—Fuel cells with solid electrolytes
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3201—Alkali metal oxides or oxide-forming salts thereof
    • C04B2235/3203—Lithium oxide or oxide-forming salts thereof
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/327—Iron group oxides, their mixed metal oxides, or oxide-forming salts thereof
    • C04B2235/3272—Iron oxides or oxide forming salts thereof, e.g. hematite, magnetite
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
    • C04B2235/74—Physical characteristics
    • C04B2235/79—Non-stoichiometric products, e.g. perovskites (ABO3) with an A/B-ratio other than 1
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/136—Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

Definitions

  • This invention relates to an anion-deficient lithium transition-metal phosphate as an electrode-active material, method for preparing the same, and electrochemical device using the same.
  • Lithium secondary batteries have advantages of light weight and high capacity as compared with other secondary batteries such as nickel-cadmium batteries (Ni//Cd) and nickel-metal hydride batteries (Ni//MH). Accordingly, lithium secondary batteries are used as power sources of electronic instruments and appliances such as mobile phones, laptop computers, game devices, and wireless cleaners. Recently, their application field has been broadening to high-capacity batteries for electric bicycles, electric scooters, service robots, electric cars, and electricity storage devices for power plants.
  • Lithium secondary batteries have generally been made by employing lithium cobaltate (LiCoO 2 as a cathode-active material, carbon as an anode-active material, and lithium hexafluorophosphate (LiPF 6 ) as an electrolyte.
  • LiCoO 2 lithium cobaltate
  • carbon carbon as an anode-active material
  • LiPF 6 lithium hexafluorophosphate
  • cobalt as the main component of lithium cobaltate (LiCoO 2 suffers from unstable supply and demand, and its cost is high. Thus, it is economically unfeasible to apply cobalt to large-size lithium secondary batteries which require a large amount of cobalt.
  • lithium manganate (LiMn 2 O 4 ) of spinel structure where cobalt is substituted by other transition metals of low cost
  • lithium transition metal polyanion compounds represented by lithium iron phosphate (LiFePO 4 ) of olivine structure are also undergoing commercialization.
  • Lithium transition-metal phosphates of olivine structure have a stable crystal structure, are highly stable to chemical reactions, and have advantages of high capacity, long life, and low cost. Nevertheless, their commercialization has not progressed easily due to low electron conductivity, low ion conductivity, and by-products formed from side reactions. Especially, the composition and crystal structure of lithium transition-metal phosphate are prone to change depending on its preparation method. Thus, it is difficult to prepare a desired composition and crystal structure, or to prepare fine particles having a uniform composition and crystal structure, or to prevent the generation of a compound containing impurities having an undesired oxidation state. These problems of the conventional technology deteriorate the characteristics of the material and batteries, resulting in low productivity, low reliability, and low cost-effectiveness and have been posing an obstacle to the commercialization of lithium transition-metal phosphates.
  • lithium manganese phosphate LiMnPO 4
  • impurities such as Mn 3 O 4 , Mn 2 O 3 , MnO 2 MnP, and Mn 3 (PO 4 ) 4 are additionally generated.
  • Most of the manganese in the impurities has an oxidation state exceeding 2, because manganese electrostructurally tends to have an oxidation state of +3 or greater, and manganese can be easily oxidized in the course of production and application.
  • a lithium manganese phosphate containing manganese ions of a +3 oxidation state or greater does not have a perfect olivine structure but contains impurities.
  • a lithium manganese phosphate containing manganese of an oxidation state of +3 or greater is inferior to a lithium manganese phosphate containing only manganese of a +2 oxidation state in characteristics as a battery material. Therefore, efforts have been made to prevent the formation of manganese of an oxidation state of +3 or greater.
  • the present invention provides anion-deficient lithium transition-metal phosphates in order to overcome the problems of conventional technology.
  • Korean Patent Application No. 2009-0005540 discloses anion-deficient lithium iron phosphate represented by Lh 1-x Fe(PO 4 ) 1-y and its preparation method.
  • the compound of the present invention is different from that of said Korean patent application in that the former essentially contains at least one element selected from the group consisting of the Group 2 and Group 13 elements of the periodic table, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Y, Zr, Nb, and Mo.
  • lithium transition-metal phosphates are referred to in published literature, they are different from the compound of the present invention in that they are not anion-deficient compounds but cation-excessive or cation-deficient compounds.
  • EP-A-1,094,532 describes a method for preparing a compound of the formula Li x MyPO 4 , in which x is greater than 0 and less than or equal to 2, y is greater than or equal to 0.8 and less than or equal to 1.2, and M includes at least one metal having 3d orbitals.
  • EP-A-1,094,533 and Korean Patent Application Laying-open No. 2001-0025117 describe a compound represented by the formula Li x M y PO 4 , in which x is greater than 0 and less than or equal to 2, and y is greater than or equal to 0.8 and less than or equal to 1.2, with M containing a 3d transition state, and the grains of Li x M y PO 4 are no greater in size than 10 micrometers.
  • U.S. Patent Application Publication No. 2006/0263286A1 and Japanese Patent Application Laying-open No. 2006-131485 disclose a preparation method of olivine Li 1+x Fe 1+y PO 4 , wherein -0.2 ⁇ x ⁇ 0.2 and -0.2 ⁇ y ⁇ 0.2.
  • U.S. Patent Application Publication No. 2007/0207080A1 discloses a method for preparing a Li x M y PO 4 compound having an olivine structure.
  • the method includes: preparing a solution containing transition metal M ions, Li + ions and PO 4 3- ions; drying the solution to form particles of a starting material; and forming the particles of the starting material into particles of the Li x M y PO 4 compound with an olivine structure, in which 0.8 ⁇ x ⁇ 1.2 and 0.8 ⁇ y ⁇ 1.2, and coating the particles of the Li x M y PO 4 compound with a carbon layer thereon.
  • PCT Publication No. WO 2003/077335 and Korean Patent Application Laying-open No. 2004-0094762 disclose an electrode-active material having the formula A a+x M b P 1-x Si x O 4 , wherein A is selected from the group consisting of Li, Na, K, and mixtures thereof, and 0 ⁇ a ⁇ 1.0 and 0 ⁇ x ⁇ 1; M comprises one or more metals, comprising at least one metal which is capable of undergoing oxidation to a higher valence state, where 0 ⁇ b ⁇ 2; and wherein M, a, b, and x are selected so as to maintain electroneutrality of said compound.
  • the lithium compounds referred to in the above literature are cation-deficient or cation-excessive compounds where the molar ratio of the anion PO 4 3- is fixed at 1 and the molar ratio of the cation M varies as in Li x M y PO 4 , and thus they are different from the anion-deficient non-stoichiometric lithium transition-metal phosphates of the present invention and cannot fundamentally solve the problems of the conventional technology.
  • a ceramic material such as lithium transition-metal phosphate is an ionic compound which comprises a cation (M y+ ) and an anion (X y- ), and non-stoichiometric ionic compounds may have four types of point defects, as follows:
  • the first type is a cation-excessive non-stoichiometric compound represented by M 1+z X.
  • the molar ratio of the anion (X y- ) is 1, which means that all the lattice points of the anion are filled.
  • the molar ratio 1+z of the cation M y+ means that all cation lattice points are filled and, in addition, the excessive z mol of the cation M y+ is positioned at interstitial sites between lattice points. This type of point defect is called an interstitial cation defect.
  • the second type is a cation-deficient non-stoichiometric compound represented by M 1-z X.
  • the molar ratio of the anion (X y- ) is 1, which means that all the lattice points of the anion are filled.
  • the molar ratio 1-z of the cation M y+ means that all cation lattice points are not filled but, instead, z mol of the cation lattice points remain as vacancies.
  • This type of point defect is a cation vacancy defect.
  • the third type is an anion-deficient non-stoichiometric compound represented by MX 1-z .
  • the molar ratio of the cation (M y+ ) is 1, which means that all the lattice points of the cation are filled.
  • the molar ratio 1-z of the anion X y- means that all anion lattice points are not filled but, instead, z mol of the anion lattice points remain as vacancies.
  • This type of point defect is an anion vacancy defect.
  • the fourth type is an anion-excessive non-stoichiometric compound represented by MX 1+z .
  • the molar ratio of the cation (M y+ ) is 1, which means that all the lattice points of the cation are filled.
  • the molar ratio 1+z of the anion X y- means that all anion lattice points are filled and, in addition, the excessive z mol of the anions are positioned at interstitial sites between lattice points.
  • This type of point defect is an interstitial anion defect.
  • the object of the present invention is to provide an anion-deficient lithium transition-metal phosphate, which shows high ion conductivity, contains a decreased amount of impurities which are not electrochemically active, and has improved characteristics as an electro-active material.
  • the present invention is also to provide a method for preparing an anion-deficient lithium transition-metal phosphate, and electrochemical device using the same.
  • the present invention is based on the surprising and unexpected discovery that the electrochemical utility and performance of a lithium transition-metal phosphate can be strikingly improved by controlling the amount and distribution of anion vacancies.
  • a compound of the present invention is an anion-deficient lithium iron phosphate represented by the following chemical formula 1: Li 1 - x ⁇ M ⁇ PO 4 1 - y wherein 0 ⁇ x ⁇ 0.15, 0 ⁇ y ⁇ 0.05, and M is represented by the following formula 2 M A a ⁇ M B b ⁇ M T t ⁇ Fe 1 - a + b + t wherein M A is at least one element selected from the group consisting of the Group 2 elements of the periodic table, M B is at least one element selected from the group consisting of Group 13 elements of the periodic table, M T is at least one element selected from the group consisting of Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Y, Zr, Nb, and Mo, and wherein 0 ⁇ a ⁇ 1, 0 ⁇ b ⁇ 0.575, 0 ⁇ t ⁇ 1, 0 ⁇ (a+b) ⁇ 1, and 0 ⁇ (a+b+t) ⁇ 1.
  • the invention provides a method for preparing an anion-deficient lithium transition-metal phosphate comprising: preparing a precursor of lithium transition-metal phosphate; mixing said precursor with water under reaction conditions of 200 ⁇ 700°C and 180 ⁇ 550bar to produce an anion-deficient lithium transition-metal phosphate; and calcining, or granulating and calcining the resultant compound.
  • lithium transition-metal phosphates produced by conventional methods have fundamental drawbacks of low electron conductivity, i.e., low lithium ion diffusion rates. Further, because the oxidation states of transition metals are hard to control in the course of preparation and application, impurities which are not electrochemically active are easily formed. In the lithium transition-metal phosphates of the present invention, such drawbacks are fundamentally resolved by anion vacancies generated due to the shortage of anions.
  • the diffusion routes of lithium ions are enlarged and the repulsive force between lithium ions in the vicinity of vacancies and transition metal cations promotes lithium ion diffusion during the deintercalation of lithium ions, resulting in increasing the lithium diffusion rate and ion conductivity.
  • the concentration gradient of lithium ions from the surface to the center of a particle becomes relatively gentle, the resistance caused by concentration polarization is decreased, and output characteristics are increased, leading to improved properties of the electrode material.
  • the oxidation number of metal cations decreases. Accordingly, the anion vacancies in the crystal improve the properties of electrode-active material by suppressing the generation of impurities of low electrochemical activity caused by oxidation of transition metals.
  • an anion-deficient non-stoichiometric lithium transition-metal phosphate of the present invention as compared with conventional lithium transition-metal phosphates, has high ion conductivity and chemical stability, provides improved output, high capacity, and long life for electrochemical devices such as secondary batteries.
  • a method of the present invention as compared with conventional methods, provides an easy way to produce an anion-deficient non-stoichiometric lithium transition-metal phosphate, and realizes high productivity, high reliability, and high cost-effectiveness.
  • a compound of the present invention represented by Li 1-x M(PO 4 ) 1-y (0 ⁇ x ⁇ 0.15, 0 ⁇ y ⁇ 0.05) is anion-deficient lithium transition-metal phosphate, wherein the molar ratio of the cation M is 1 and the molar ratio of the anion PO 4 is less than 1.
  • the present compound is compositionally and structurally distinct from the conventional lithium transition-metal phosphates.
  • the molar ratio of the lithium ions means the ratio of the lithium ions which are constituents of the anion-deficient lithium transition-metal phosphate.
  • an excessive amount of a lithium precursor is introduced as a reactant.
  • the molar ratio of lithium in a synthesized lithium iron phosphate may be greater than that in the above chemical formula.
  • lithium introduced for the above purposes does not exist in the anion-deficient lithium transition-metal phosphate of the present invention but is present as an impurity having electrochemical activity.
  • a representative example of such lithium ions is those existing in the form of a surface defect on a crystal.
  • y corresponds to the amount of anion vacancies.
  • the average oxidation number of M should decrease or the amount of lithium ions of a +1 oxidation state should decrease.
  • the amount of Li should decrease by three times the amount of decrease of PO 4 in order to maintain electroneutrality.
  • the formation of vacancies of the anion PO 4 and vacancies of the cation Li in the amount of three times the PO 4 vacancies is called a Schottky defect, which is a typical mechanism of forming vacancies.
  • x may be -1 ⁇ x ⁇ 1.
  • a preferred range of x is 0 ⁇ x ⁇ 0.15.
  • the value of y which indicates the amount of anion vacancies, is 0 ⁇ y ⁇ 0.05. If y ⁇ 0, the compound is not anion-deficient, and if y>0.05, the structure of the compound is unstable and electrochemical activity deteriorates.
  • the value of y is 0.01 ⁇ y ⁇ 0.05, more preferably 0.02 ⁇ y ⁇ 0.05, and most preferably 0.03 ⁇ y ⁇ 0.05.
  • M A has a +2 oxidation state
  • M B has a +3 oxidation state
  • Fe generally has an oxidation state of +2 or +3
  • M T may have various oxidation states of +1 to +7. Accordingly, according to the amounts of M A , M B , M T , and Fe, the oxidation numbers of M T and Fe change so that electroneutrality is maintained.
  • the average oxidation number of cations having different oxidation numbers is denoted as v, when 0 ⁇ x ⁇ 0.15 and 0 ⁇ y ⁇ 0.05, the average oxidation number v is 1.85 ⁇ v ⁇ 2.15. If 0.01 ⁇ y ⁇ 0.05, then 1.85 ⁇ v ⁇ 2.12. Further, if 0.02 ⁇ y ⁇ 0.05, then 1.85 ⁇ v ⁇ 2.09, and if 0.03 ⁇ y ⁇ 0.05, then 1.85 ⁇ v ⁇ 2.06.
  • v T the average oxidation number of M T
  • v F the average oxidation number of Fe
  • v is expressed by the following equation 1, and the range of v, which is limited by the requirement for electroneutrality, limits the amounts of M A , M B , M T , and Fe and the oxidation numbers of M T and Fe.
  • v 2 ⁇ a + 3 ⁇ b + v T ⁇ t + v F 1 - a + b + t
  • M A is at least one selected from Mg and Ca, more preferably, it is Mg. Since M A has a +2 oxidation state, the compound can have a stable structure when 0 ⁇ a ⁇ 1. However, if a is 1, the compound is of no use as electrode-active material because it has no electrochemical activity, and thus the range of a is limited to 0 ⁇ a ⁇ 1. Also, the range of a is preferably 0 ⁇ a ⁇ 0.30, and more preferably 0 ⁇ a ⁇ 0.15.
  • the Group 13 elements which constitute M B lower the average oxidation number of the transition metal M T , prevent oxidation, improve electrochemical activity, and suppress the generation of impurities.
  • M B is at least one selected from B, Al, and Ga, and more preferably it is Al. Since M B has a +3 oxidation state, it cannot be doped beyond a certain degree.
  • the greatest amount of M B can be dissolved when the average oxidation number of M T is +1, and in this case, when 0 ⁇ x ⁇ 0.15 and 0 ⁇ y ⁇ 0.05, the upper limit of b, which denotes the amount of M B , is 0.575.
  • the range of b is preferably 0 ⁇ b ⁇ 0.20 and more preferably 0 ⁇ b ⁇ 0.10.
  • M T is at least one element selected from Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Y, Zr, Nb and Mo, which are the elements of periods 4 and 5 of the periodic table excluding Fe. Transition metals have various oxidation numbers ranging from +1 to +7 and various electrochemical activities. Depending on which transition metals are employed, most of the fundamental properties of an electrode-active material (theoretical capacity and potential) are greatly affected. Accordingly, M T can be constituted in accordance with a required battery system.
  • M T is at least one element selected from Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Zr, Nb, and Mo, and more preferably it is at least one element selected from Mn, Co, and Ni.
  • An anion-deficient lithium transition-metal phosphate of the present invention necessarily contains at least one element selected from the group consisting of Groups 2 and 13 elements, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Y, Zr, Nb and Mo.
  • An anion-deficient lithium transition-metal phosphate of chemical formula 1 is preferably crystalline.
  • compounds may have various crystal structures, but olivine structure is preferred.
  • An anion-deficient lithium transition-metal phosphate of the present invention can be used as an electrode-active material for secondary batteries, memory devices, and capacitors including hybrid capacitors (P-EDLC), and other electrochemical devices, preferably as a cathode-active material for secondary batteries.
  • P-EDLC hybrid capacitors
  • An electrode can be made in conventional ways well-known in the art.
  • an electrode can be made by mixing an anion-deficient lithium transition-metal phosphate as a cathode-active material with a binder to prepare an electrode slurry, and coating the obtained electrode slurry on a current collector.
  • a conducting agent can optionally be used.
  • the present invention provides an electrochemical device comprising (a) a cathode containing an anion-deficient lithium transition-metal phosphate, (b) an anode, (c) a separator, and (d) an electrolyte.
  • An electrochemical device of the present invention can be made, for example, according to any conventional method known in the art, by interposing a porous separator between a cathode and an anode and adding an electrolyte.
  • an anode, an electrolyte, and a separator which are used together with a cathode of the present invention, and those conventionally used in electrochemical devices can be adopted.
  • the electrochemical devices provided by the present invention include all devices wherein an electrochemical reaction occurs, for example, various secondary batteries, memory devices, and capacitors including hybrid capacitors (P-EDDC).
  • P-EDDC hybrid capacitors
  • the secondary batteries include lithium secondary batteries such as lithium metal secondary batteries, lithium ion secondary batteries, lithium ion polymer secondary batteries, and lithium metal polymer secondary batteries.
  • An anion-deficient lithium transition-metal phosphate of the present invention shows high ion conductivity and good physical and chemical stability, and thereby it provides high capacity, high power, long life, and improved output characteristics for batteries adopting it, and enables the fabrication of a more homogeneous electrode plate, reducing the formation of defective batteries.
  • An anion-deficient lithium transition-metal phosphate of the present invention may be synthesized based on a hydrothermal synthesis method that uses supercritical or subcritical water, by controlling reaction variables, such as the mixing ratios of reactants, reaction temperature, and reaction pressure.
  • a method of the present invention requires only a few seconds at a high temperature and a high pressure for synthesizing an anion-deficient lithium transition-metal phosphate. Also, the present method does not require a separate process for mixing a lithium source at a calcination step and does not require heat treatment time for lithium ion diffusion, because the lithium transition-metal phosphate already contains lithium ions before the calcination step. Accordingly, time needed for synthesizing a final electrode-active material can be shortened.
  • a method of the present invention enables the easy preparation of anion-deficient lithium transition-metal phosphates.
  • an anion-deficient lithium transition-metal phosphate of the present invention can be prepared according to a method comprising the following steps:
  • any compound can be used as long as it is a salt containing the metal M of chemical formula 1 and can be ionized.
  • Preferred ones are water-soluble compounds.
  • Non-limiting examples of the metal M's precursors include nitrates, sulfates, acetates, carbonates, oxalates, halides, oxides, hydroxides, alkoxides, and combinations thereof which contain the metal M. Particularly, nitrates, sulfates, and acetates are preferred.
  • any ionizable compound containing the phosphate group can be used.
  • Preferred are water-soluble compounds.
  • Non-limiting examples of the phosphate compounds include phosphoric acid, ammonium phosphate, hydrogen ammonium phosphate, lithium phosphate, phosphate containing at least one constituent of the metal M, and combinations thereof. Particularly, phosphoric acid is preferred.
  • Any alkalinizing agent can be used as long as it makes a reaction solution alkaline.
  • the alkalinizing agents are alkali metal hydroxides, alkaline earth metal hydroxides, ammonium hydroxide, ammonium compounds, TRAH (tetra-alkyl ammonium hydroxide) and mixtures thereof. Particularly, alkali metal hydroxides and ammonium hydroxide are preferred.
  • any compound can be used as long as it is a water-soluble salt containing lithium and is ionizable.
  • Non-limiting examples thereof include lithium hydroxide, lithium nitrate, lithium sulfate, lithium acetate, and mixtures thereof.
  • lithium hydroxide is preferred because it serves as a source of lithium and increases alkalinity.
  • the molar ratio of Li to M is preferably 1.0 to 20, and more preferably 1.0 to 10. If the value of Li/M is too low, only a small amount of lithium participates in the reaction to form an anion-deficient lithium transition-metal phosphate, and the precursors of the metal M which do not participate in the reaction with lithium will form, for example, impurities like oxides, and thus reduces the purity of the desired product. Meanwhile, if said value is too high, the lithium excessively added should be recovered from a discharged solution or wasted, thereby lowering economic efficiency.
  • the alkali equivalent ratio of a mixture containing a precursor of the metal M, phosphate compound, alkalinizing agent and lithium precursor is preferably 1 to 10, but is not limited thereto.
  • the alkali equivalent ratio is defined as the ratio between the number of equivalents of hydroxyl ions and the number of equivalents of acid groups (NO 3 SO 4 etc.) in the mixture. If the alkali equivalent ratio is too low, impurities will be present in the product, and if it is too high, alkaline content in wastewater will be excessively high.
  • metal M's precursor, phosphate compound, alkalinizing agent, and lithium precursor there is no special limitation to the method and order of mixing.
  • they can be mixed with water all at once, or they can be separately introduced into water, or the metal M's precursor, phosphate compound, alkalinizing agent, and lithium precursor can be mixed first and then the mixture can be introduced into water.
  • Reaction temperature and pressure should be suitable so that the anion-deficient lithium transition-metal phosphate of a desired composition can be produced.
  • a supercritical or subcritical condition used herein is a condition where temperature ranges from 200 to 700 °C and pressure from 180 to 550 bar. Preferably, said condition should be maintained continuously.
  • a continuous reactor type is preferred.
  • a reaction temperature below 200°C makes it difficult to obtain a single-phase high-crystallinity anion-deficient lithium transition-metal phosphate, and a temperature above 700°C increases the cost of an apparatus for synthesizing the compound.
  • hydroxides of alkali metals such as lithium, sodium, and potassium have high solubility in water at ambient temperature and atmospheric pressure, the solubility markedly decreases if the density of water decreases due to high temperature and high pressure.
  • LiOH in order to significantly decrease its solubility, it is necessary to maintain the pressure between 180 and 550bar and the temperature between 200 and 700°C simultaneously.
  • pH during the reaction is preferably greater than 4.0 and equal to or less than 12.0. If the pH is 4.0 or less, the produced anion-deficient lithium transition-metal phosphate, undesirably, dissolves at the low pH. Meanwhile, a pH above 12.0 causes by-products, corrosion of apparatus, and waste of alkalinizing agents, and necessitates separate steps for washing out an excessive amount of alkalinizing agents and for treating a discharged solution, thereby resulting in low economic efficiency.
  • Mixing is preferably carried out in a continuous mixer such as a tube-type mixer.
  • a continuous mixer such as a tube-type mixer.
  • anion-deficient lithium transition-metal phosphate is uniformly formed.
  • reaction product is subject to cooling, concentrating and drying.
  • a concentrate Before a concentrate is subject to drying, it may be washed with clean water to remove impurity salts and ionic impurities which can remain in the concentrate.
  • the average size of the primary particles prepared at step (b) is 0.01 ⁇ 5 ⁇ m, preferably 0,01 ⁇ 1 ⁇ m and more preferably 0.01 to 0.5 ⁇ m.
  • An anion-deficient lithium transition-metal phosphate produced at step (b) has low crystallinity and the average size of the primary particles is so small that they are not suitable for use as a cathode-active material for secondary batteries. Accordingly, step (c) improves the crystallinity and controls the size to be suitable for use as a cathode-active material.
  • Preferred size of the cathode-active material for secondary batteries is 1 to 100 ⁇ m.
  • Granulation can be conducted simultaneously with drying using various methods known in the art, such as spray drying, fluidized-bed drying, vibration drying. Particularly, spray drying is preferred because it increases the tap density of granules by making the granules spherical.
  • Calcination increases the crystallinity of an anion-deficient lithium transition-metal phosphate and improves adhesion between crystal particles. Calcination is preferably carried out right after said step (b). Granulation and subsequent calcination are carried out preferably in a continuous manner, because in this case, primary particles, which constitute granules, grow with crystallographic stability. If calcination is not performed, crystals will not be stabilized, and the unstable surface collapses, which causes a serious deterioration in the initial charge and discharge capacities of batteries. Also, without calcination, an electrode-active material will undesirably have a large specific surface area, low tap density, and, as a result, low capacity per volume.
  • Calcining temperature and time are not limited to specific ranges, but are preferably 300 to 1,200°C and 1 to 48 hours, respectively. If the temperature is too low or the time is too short, sintering among primary particles may not occur sufficiently, which results in primary particles having low crystallinity and a large specific surface area, and showing a low tap density in an electrode. A compound of low crystallinity changes to a different material during charge and discharge, thereby deteriorating battery performances, such as charge and discharge capacities, power output, and life. Meanwhile, if the temperature is too high or the time is too long, excessive sintering occurs, which brings about disadvantages such as phase decomposition, and processing cost increases.
  • additives selected from the group consisting of binders, sintering aids, doping agents, coating agents, reducing agents, oxidizing agents, carbon precursors, metal oxides, and lithium compounds.
  • a binder can be used to make granules spherical and improve particle size distribution.
  • Non-limiting examples of the binders include water, ammonia water, PVA (poly vinyl alcohol), and mixtures thereof.
  • a sintering aid can be used during the calcination of granules at a high temperature to lower the sintering temperature or to increase sintering density.
  • the sintering aids include metal oxides, such as boron oxide, magnesium oxide and aluminum oxide, and precursors thereof; and lithium compounds, such as lithium fluoride, lithium hydroxide and lithium carbonate, and precursors thereof.
  • a doping agent and a coating agent are used to improve the durability of an anion-deficient lithium transition-metal phosphate.
  • Non-limiting examples thereof include metal oxides, such as magnesium oxide, aluminum oxide, titanium oxide, zirconium oxide, and precursors thereof.
  • a reducing agent or an oxidizing agent can be used to control a certain step to a reducing or oxidizing atmosphere.
  • a suitable reducing agent can be used to increase electron conductivity and to suppress transition-metal oxidation or for other purposes.
  • the reducing agents include hydrazine, sodium phosphite, sodium sulfite, sodium nitrite, potassium iodide, sucrose, fructose, oxalic acid, ascorbic acid, hydrogen, carbon, hydrocarbon, and mixtures thereof.
  • Non-limiting examples of the oxidizing agents include oxygen, chlorine, bromine, hydrogen peroxide, permanganic acid, permanganate, hypochlorite, chlorate, ozone, and their mixtures.
  • An acid is used to promote a reaction.
  • the acids include phosphoric acid, pyrophosphoric acid, polyphosphoric acid, nitric acid, sulfuric acid, hydrochloric acid, acetic acid, oxalic acid, compounds of these acids, and mixtures thereof.
  • Carbon precursors can be used for coating the surface of an anion-deficient lithium transition-metal phosphate to improve electron conductivity.
  • Non-limiting examples of the carbon precursors include graphite, sucrose, fructose, oxalic acid, ascorbic acid, starch, cellulose, polyvinyl alcohol (PVA), and polyethylene glycol (PEG) and mixtures thereof.
  • a lithium compound can be added in a calcination step to increase lithium content in an anion-deficient lithium transition-metal phosphate.
  • Non-limiting examples of the lithium compound include lithium fluoride, lithium hydroxide, lithium carbonate, lithium nitrate, lithium acetate, and mixtures thereof.
  • composition of an anion-deficient lithium transition-metal phosphate is affected by various factors, such as the mixing ratios of a metal precursor, a phosphate compound, an alkalinizing agent, a lithium precursor and water; the pH of the mixture; and reaction temperature and pressure, etc. By controlling these factors, the composition of a compound can be controlled. Although there can be an optimal combination of said factors for obtaining a compound of a specific composition, the number of combinations for synthesizing compounds of the same composition is not limited to one. A person of skill in the art would know specific combinations of the above factors for obtaining a certain composition without undue experimentation.
  • Example 1 Preparation of an anion-deficient compound wherein the metal M is a combination of Mn and Fe
  • a first water solution was prepared by dissolving 0.25 mol of manganese sulfate (MnSO 4 and 0.75 mol of ferrous sulfate (FeSO 4 as precursors of the metal M, 1 mol of phosphoric acid as a phosphate compound, and 27.8g of sucrose as a reducing agent in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia as an alkalinizing agent and 2 mol of lithium hydroxide as a lithium precursor in 1.2 L of water.
  • the pH of the mixture in the mixer was 8.5.
  • FIG. 1 is a SEM photograph of granulated particles at a magnification of 1,000 times and shows that the particle size is 5 ⁇ 30 ⁇ m.
  • Figure 2 is a SEM photograph which was taken of part of a granule at a magnification of 50,000 times and shows nanometer-size ultrafine particles which constitute the granule.
  • Figure 3 shows the result of Rietveld refinement performed on X-ray diffraction patterns of the synthesized compound.
  • the occupancy ratios of the ions in a unit cell were computed by modeling the result of Rietveld refinement, and it was found that the compound was Li 0.89 (Mn 0.25 Fe 0 . 75 )(PO 4 ) 0.96 .
  • Li may be added in an excessive amount when preparing a lithium transtion-metal phosphate. Such excessively added Li was excluded from the amount of lithium in calculating the above molar ratio of Li. The molar ratio counted only the Li which constituted the anion-deficient lithium transtion-metal phosphate of the present invention. The molar ratio of Li was calculated in the same way in the other Examples given below.)
  • Example 2 Preparation of an anion-deficient compound wherein the metal M is a combination of Mn and Fe
  • a first water solution was prepared by dissolving 0.50 mol of manganese sulfate, 0.50 mol of ferrous sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • the final product was assayed with an inductively coupled plasma (ICP) spectrometer and the compound was found to be Li 0.90 (Mn 0.50 Fe 0.50 )(PO 4 ) 0.96 .
  • ICP inductively coupled plasma
  • Example 3 Preparation of an anion-deficient compound wherein the metal M is a combination of Mn and Fe
  • a first water solution was prepared by dissolving 0.75 mol of manganese sulfate, 0.25 mol of ferrous sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • the final product was assayed with an inductively coupled plasma (ICP) spectrometer, and the compound was found to be Li 0.90 (Mn 0.75 Fe 0.25 )(PO 4 ) 0.97 .
  • ICP inductively coupled plasma
  • a first water solution was prepared by dissolving 1 mol of manganese sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • Example 5 Preparation of an anion-deficient compound wherein the metal M is a combination of Co and Fe
  • a first water solution was prepared by dissolving 0.25 mol of cobalt nitrate (Co(NO 3 ) 2 ), 0.75 mol of ferrous sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • Example 6 Preparation of an anion-deficient compound wherein the metal M is a combination of Co and Fe
  • a first water solution was prepared by dissolving 0.50 mol of cobalt nitrate, 0.50 mol of ferrous sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • the final product was assayed with an inductively coupled plasma (ICP) spectrometer, and the compound was found to be Li 0.91 (Co 0.50 Fe 0.50 )(PO 4 ) 0.97 .
  • ICP inductively coupled plasma
  • Example 7 Preparation of an anion-deficient compound wherein the metal M is a combination of Co and Fe
  • a first water solution was prepared by dissolving 0.75 mol of cobalt nitrate, 0.25 mol of ferrous sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • the final product was assayed with an inductively coupled plasma (ICP) spectrometer, and the compound was found to be Li 0.90 (Co 0.75 Fe 0.25 )(PO 4 ) 0.97 .
  • ICP inductively coupled plasma
  • Example 8 Preparation of an anion-deficient compound wherein the metal M is Co
  • a first water solution was prepared by dissolving 1 mol of cobalt nitrate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • Example 9 Preparation of an anion-deficient compound wherein the metal M is a combination of Ni and Fe
  • a first water solution was prepared by dissolving 0.25 mol of nickel nitrate (Ni(NO 3 ) 2 ), 0.75 mol of ferrous sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • Example 10 Preparation of an anion-deficient compound wherein the metal M is a combination of Ni and Fe
  • a first water solution was prepared by dissolving 0.50 mol of nickel nitrate, 0.50 mol of ferrous sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • the final product was assayed with an inductively coupled plasma (ICP) spectrometer, and the compound was found to be Li 0.92 (Ni 0.50 Fe 0.50 )(PO 4 ) 0.97 .
  • ICP inductively coupled plasma
  • Example 11 Preparation of an anion-deficient compound wherein the metal M is a combination of Ni and Fe
  • a first water solution was prepared by dissolving 0.75 mol of nickel nitrate, 0.25 mol of ferrous sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • the final product was assayed with an inductively coupled plasma (ICP) spectrometer, and the compound was found to be Li 0.92 (Ni 0.75 Fe 0.25 )(PO 4 ) 0.98 .
  • ICP inductively coupled plasma
  • a first water solution was prepared by dissolving 1 mol of nickel nitrate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • Example 13 Preparation of an anion-deficient compound wherein the metal M is a combination of Mn, Co, and Ni
  • a first water solution was prepared by dissolving 1/3 (one third) mol of manganese sulfate, 1/3 mol of cobalt nitrate, 1/3 mol of nickel nitrate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • Example 14 Preparation of an anion-deficient compound wherein the metal M is a combination of Mn, Co, Ni, and Fe
  • a first water solution was prepared by dissolving 0.25 mol of manganese sulfate, 0.25 mol of cobalt nitrate, 0.25 mol of nickel nitrate, 0.25 mol of ferrous sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • Example 15 Preparation of an anion-deficient compound wherein the metal M is a combination of Mg and Fe
  • a first water solution was prepared by dissolving 0.07 mol of magnesium sulfate (MgSO 4 ), 0.93 mol of ferrous sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • the final product was assayed with an inductively coupled plasma (ICP) spectrometer, and the compound was found to be Li 0.88 (Mg 0.07 Fe 0.93 )(PO 4 ) 0.96 .
  • ICP inductively coupled plasma
  • Example 16 Preparation of an anion-deficient compound wherein the metal M is a combination of Mg and Mn
  • a first water solution was prepared by dissolving 0.10 mol of magnesium sulfate, 0.90 mol of manganese sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • the final product was assayed with an inductively coupled plasma (ICP) spectrometer, and the compound was found to be Li 0.92 (Mg 0.10 Mn 0.90 )(PO 4 ) 0.97 .
  • ICP inductively coupled plasma
  • Example 17 Preparation of an anion-deficient compound wherein the metal M is a combination of Al, Mn, and Fe
  • a first water solution was prepared by dissolving 0.03 mol of aluminum nitrate (Al(NO 3 ) 3 ), 0.78 mol of manganese sulfate, 0.19 mol of ferrous sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • the final product was assayed with an inductively coupled plasma (ICP) spectrometer, and the compound was found to be Li 0.85 (Al 0.33 Mn 0.78 Fe 0.19 )(PO4) 0.98 .
  • ICP inductively coupled plasma
  • Example 18 Preparation of an anion-deficient compound wherein the metal M is a combination of Mn, Co, Ni, and Fe
  • a first water solution was prepared by dissolving 0.25 mol of manganese sulfate, 0.25 mol of cobalt nitrate, 0.25 mol of nickel nitrate, 0.25 mol of ferrous sulfate, 1.1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • the final product was assayed with an inductively coupled plasma (ICP) spectrometer, and the compound was found to be Li 0.94 (Mn 0.25 Co 0.25 Ni 0.25 Fe 0.25 )(PO 4 ) 0.98 .
  • ICP inductively coupled plasma
  • Example 19 Preparation of an anion-deficient compound wherein the metal M is a combination of Mn, Co, Ni, and Fe
  • a first water solution was prepared by dissolving 0.25 mol of manganese sulfate, 0.25 mol of cobalt nitrate, 0.25 mol of nickel nitrate, 0.25 mol of ferrous sulfate, 1.2 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 1.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • the pH of the mixture in the mixer was 6.6.
  • the final product was assayed with an inductively coupled plasma (ICP) spectrometer, and the compound was found to be Li 0.97 (Mn 0.25 Co 0.25 Ni 0.25 Fe 0.25 )(PO 4 ) 0.99 .
  • ICP inductively coupled plasma
  • Example 20 Preparation of an anion-deficient compound wherein the metal M is a combination of Mn, Co, Ni, and Fe
  • a first water solution was prepared by dissolving 0.25 mol of manganese sulfate, 0.25 mol of cobalt nitrate, 0.25 mol of nickel nitrate, 0.25 mol of ferrous sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 2.0 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • the final product was assayed with an inductively coupled plasma (ICP) spectrometer, and the compound was found to be Li 0.89 (Mn 0.25 Co 0.25 Ni 0.25 Fe 0.25 )(PO 4 ) 0.96 .
  • ICP inductively coupled plasma
  • Example 21 Preparation of an anion-deficient compound wherein the metal M is a combination of Mn, Co, Ni, and Fe
  • a first water solution was prepared by dissolving 0.25 mol of manganese sulfate, 0.25 mol of cobalt nitrate, 0.25 mol of nickel nitrate, 0.25 mol of ferrous sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 2.5 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • the pH of the mixture in the mixer was 9.5.
  • the final product was assayed with an inductively coupled plasma (ICP) spectrometer, and the compound was found to be Li 0.86 (Mn 0.25 Co 0.25 Ni 0.25 Fe 0.25 )(PO 4 ) 0.95 .
  • ICP inductively coupled plasma
  • Comparative Example 1 Preparation of a stoichiometric compound wherein the metal M is a combination of Mn and Fe
  • Comparative Example 2 Preparation of a stoichiometric compound wherein the metal M is a combination of Mn and Fe
  • a stoichiometric lithium manganese iron phosphate was prepared by processing the above materials in the same way under the same conditions as in steps (a), (b), and (c) of Comparative Example 1.
  • a stoichiometric lithium manganese iron phosphate was prepared by processing the above materials in the same way under the same conditions as in steps (a), (b), and (c) of Comparative Example 1.
  • a stoichiometric lithium manganese phosphate was prepared by processing the above materials in the same way under the same conditions as in steps (a), (b), and (c) of Comparative Example 1.
  • a first water solution was prepared by dissolving 0.25 mol of cobalt acetate (Co(CH 3 CO 2 ) 2 ) and 0.75 mol of ferrous oxalate as metal precursors, 1 mol of monoammonium phosphate (NH 4 H 2 PO 4 ) as a phosphate compound, and 0.525 mol of lithium carbonate (Li 2 CO 3 ) as a lithium precursor in distilled water.
  • a second water solution was prepared by dissolving 1 mol of citric acid as both a gelation agent and a carbon precursor in distilled water.
  • a stoichiometric lithium cobalt iron phosphate was prepared according to a conventional sol-gel method by processing the above two solutions in the order of the following steps (a), (b), and (c).
  • a first water solution was prepared by dissolving 0.50 mol of cobalt acetate, 0.50 mol of ferrous oxalate, 1 mol of monoammonium phosphate, and 0.525 mol of lithium carbonate in distilled water.
  • a second water solution was prepared by dissolving 1 mol of citric acid in distilled water.
  • a stoichiometric lithium cobalt iron phosphate was prepared by processing the above two solutions in the same way under the same conditions as in steps (a), (b), and (c) of Comparative Example 5.
  • a first water solution was prepared by dissolving 0.75 mol of cobalt acetate, 0.25 mol of ferrous oxalate, 1 mol of monoammonium phosphate, and 0.525 mol of lithium carbonate in distilled water.
  • a second water solution was prepared by dissolving 1 mol of citric acid in distilled water.
  • a stoichiometric lithium cobalt iron phosphate was prepared by processing the above two solutions in the same way under the same conditions as in steps (a), (b), and (c) of Comparative Example 5.
  • a first water solution was prepared by dissolving 1 mol of cobalt acetate, 1 mol of monoammonium phosphate, and 0.525 mol of lithium carbonate in distilled water.
  • a second water solution was prepared by dissolving 1 mol of citric acid in distilled water.
  • a stoichiometric lithium cobalt phosphate was prepared by processing the above two solutions in the same way under the same conditions as in steps (a), (b), and (c) of Comparative Example 5.
  • a first water solution was prepared by dissolving 0.25 mol nickel acetate (Ni(CH 3 CO 2 ) 2 ), 0.75 mol of ferrous oxalate, 1 mol of monoammonium phosphate, and 0.525 mol of lithium carbonate in distilled water.
  • a second water solution was prepared by dissolving 1 mol of citric acid in distilled water.
  • a stoichiometric lithium nickel iron phosphate was prepared by processing the above two solutions in the same way under the same conditions as in steps (a), (b), and (c) of Comparative Example 5.
  • Comparative Example 10 Preparation of a stoichiometric compound wherein the metal M is a combination of Ni and Fe
  • a first water solution was prepared by dissolving 0.50 mol nickel acetate, 0.50 mol of ferrous oxalate, 1 mol of monoammonium phosphate, and 0.525 mol of lithium carbonate in distilled water.
  • a second water solution was prepared by dissolving 1 mol of citric acid in distilled water.
  • a stoichiometric lithium nickel iron phosphate was prepared by processing the above two solutions in the same way under the same conditions as in steps (a), (b), and (c) of Comparative Example 5.
  • a first water solution was prepared by dissolving 0.75 mol nickel acetate, 0.25 mol of ferrous oxalate, 1 mol of monoammonium phosphate, and 0.525 mol of lithium carbonate in distilled water.
  • a second water solution was prepared by dissolving 1 mol of citric acid in distilled water.
  • a stoichiometric lithium nickel iron phosphate was prepared by processing the above two solutions in the same way under the same conditions as in steps (a), (b), and (c) of Comparative Example 5.
  • a first water solution was prepared by dissolving 1 mol of nickel acetate, 1 mol of monoammonium phosphate, and 0.525 mol of lithium carbonate in distilled water.
  • a second water solution was prepared by dissolving 1 mol of citric acid in distilled water.
  • a stoichiometric lithium nickel phosphate was prepared by processing the above two solutions in the same way under the same conditions as in steps (a), (b), and (c) of Comparative Example 5.
  • Comparative Example 13 Preparation of a stoichiometric compound wherein the metal M is a combination of Mn, Co, and Ni
  • a first water solution was prepared by dissolving 0.3 mol of manganese acetate, 0.3 mol of cobalt acetate, 0.3 mol of nickel acetate, 0.9 mol of monoammonium phosphate, and 0.473 mol of lithium carbonate in distilled water.
  • a second water solution was prepared by dissolving 0.9 mol of citric acid in distilled water.
  • a stoichiometric lithium manganese cobalt nickel phosphate was prepared according to a conventional sol-gel method by processing the above two solutions in the order of the following steps (a), (b), and (c).
  • Comparative Example 14 Preparation of a stoichiometric compound wherein the metal M is a combination of Mn, Co, Ni and Fe
  • a first water solution was prepared by dissolving 0.25 mol of manganese acetate, 0.25 mol of cobalt acetate, 0.25 mol of nickel acetate, 0.25 mol of ferrous oxalate, 1 mol of monoammonium phosphate, and 1 mol of lithium carbonate in distilled water.
  • a second water solution was prepared by dissolving 0.9 mol of citric acid in distilled water.
  • a stoichiometric lithium manganese cobalt nickel iron phosphate was prepared according to a conventional sol-gel method by processing the above two solutions in the order of the following steps (a), (b), and (c).
  • Comparative Example 15 Preparation of an anion-deficient compound wherein the metal M is a combination of Mn, Co, Ni, and Fe
  • a first water solution was prepared by dissolving 0.25 mol of manganese sulfate, 0.25 mol of cobalt nitrate, 0.25 mol of nickel nitrate, 0.25 mol of ferrous sulfate, 1 mol of phosphoric acid, and 27.8g of sucrose in 1.6 L of water.
  • a second water solution was prepared by dissolving 3 mol of ammonia and 2 mol of lithium hydroxide in 1.2 L of water.
  • Figures 3, 4 , 5, 6 , 7, 8 , 9, and 10 show the results of Rietveld refinement performed on X-ray diffraction patterns of the compounds synthesized in Examples 1, 4, 5, 8, 9, 12, 13 and 14, respectively.
  • Tables 1, 2, 3, 4, 5, 6, 7, and 8 show the positions of elements in a unit cell identified by carrying out Rietveld refinement and also show the occupancy ratios of Li, Mn, Co, Ni, Fe and P ascertained by modeling crystal structures based on the result of the Rietveld refinement.
  • the occupancy ratios of the respective elements indicated in Tables 1, 2, 3, 4, 5, 6, 7, and 8 show that the molar ratio of the metal M, i.e., the sum of the molar ratios of the metal elements excluding Li, is 1 while the molar ratio of phosphorus (P) ranges from 0.9625 to 0.9775, which is less than 1.
  • the results of ICP analysis in Examples 2, 3, 6, 7, and 10 to 21 show that the molar ratio of the metal M is 1 whereas the molar ratio of phosphorus (P) ranges from 0.95 to 0.99, which is less than 1.
  • the lithium transition-metal phosphates prepared in the working examples of the present invention are anion-deficient compounds.
  • the results of inductively coupled plasma spectroscopy show that the compounds of Comparative Examples 1 to 14 are stoichiometric compounds, which contain M and P at a molar ratio of 1:1.
  • the anion-deficient lithium transition-metal phosphates of the present invention represented by Li 1-x M(PO 4 ) 1-y , exhibit superior lithium diffusion coefficients over the stoichiometric lithium transition-metal phosphate LiMPO 4 .
  • a battery employing a compound of the present invention achieves a lower electrode resistance.
  • each of Figures 12, 13 , 14, 15 , and 16 is a Nyquist plot indicating a measured impedance on a complex plane as a function of frequency, wherein Z' and Z" are respectively the real component and the imaginary component of the impedance Z which is a complex number.
  • Electrode resistance can be calculated based on a measured impedance. A Nyquist plot indicates what types of resistance are involved. From the shapes of the plots in Figures 12 to 16 , it is understood that the electrode resistance is comprised of solid electrolyte interface resistance (SEI resistance) and charge transport resistance (CT resistance).
  • SEI resistance solid electrolyte interface resistance
  • CT resistance charge transport resistance
  • the electrode resistance of Li 0.89 (Mn 0.25 Fe 0.75 )(PO 4 ) 0.96 is 294 ⁇ , which is 2.27 times smaller than that of stoichiometric Li(Mn 0.25 Fe 0.75 )PO 4 having 669 ⁇ .
  • the electrode resistance of Li 0.91 (Co 0.25 Fe 0.75 )(PO 4 ) 0.97 is 322 ⁇ , which is 2.12 times smaller than that of stoichiometric Li(Co 0.25 Fe 0.75 )PO 4 having 683 ⁇ .
  • the electrode resistance of Li 0.91 (Ni 0.26 Fe 0.74 )(PO 4 ) 0.97 is 329 ⁇ , which is 2.17 times smaller than that of stoichiometric Li(Ni 0.25 Fe 0.75 )PO 4 having 713 ⁇ .
  • the electrode resistance of Li 0.89 (Mn 0.33 Co 0.33 Ni 0.33 )(PO 4 ) 0.96 is 313Q, which is 2.29 times smaller than that of stoichiometric Li(Mn 0.33 Co 0.33 Ni 0.33 )PO 4 having 717 ⁇ .
  • the electrode resistance of Li 0.90 (Mn 0.25 Co 0.25 Ni 0.25 Fe 0.25 )(PO 4 ) 0.97 is 315 ⁇ , which is 2.16 times smaller than that of stoichiometric Li(Mn 0.25 Co 0.25 Ni 0.25 Fe 0.25 )PO 4 having 679 ⁇ .
  • the electrode resistance decreases by 2.1 to 2.3 times regardless of the molar ratios of the elements constituting the metal M. Such decrease is due to anion vacancies, which are generated as a result of anion deficiency and facilitate lithium ion diffusion, thereby reducing the electrode resistance.
  • the fact that electrode resistance has no correlation with the composition of the metal M means that anion vacancies affect lithium ion diffusion regardless of the composition.
  • lithium ion diffusion coefficients were measured on Li 0.89 (Mn 0.25 Fe 0.75 )(PO 4 ) 0.96 of Example 1 and Li(Mn 0.25 Fe 0.75 )PO 4 of Comparative Example 1, Li 0.91 (Co 0.25 Fe 0.75 )(PO 4 ) 0.97 of Example 5 and Li(Co 0.25 Fe 0.75 )PO 4 of Comparative Example 5, Li 0.91 (Ni 0.26 Fe 0.74 )(PO 4 ) 0.97 of Example 9 and Li(Ni 0.25 Fe 0.75 )PO 4 of Comparative Example 9, Li 0.89 (Mn 0.33 Co 0.33 Ni 0.33 )(PO 4 ) 0.96 of Example 13 and Li(Mn 0.33 Co 0.33 Ni 0.33 )PO 4 of Comparative Example 13, and Li 0.90 (Mn 0.25 Co 0.25 Ni 0.25 Fe 0.25 )(PO 4 ) 0.97 of Example 14 and Li(Mn 0.25 Co 0.25 Ni 0.25 Fe 0.25 )PO 4 of Comparative Example 14.
  • Figures 17 , 18 , 19 , 20, and 21 are the measurement results, and show the dependency of lithium ion diffusion coefficient on lithium concentration.
  • Figures 17 to 21 as the charging of a battery proceeds, the number of lithium ions in an active material decreases and the lithium diffusion coefficient gradually increases. During discharge, an opposite phenomenon occurs inside the active material, i.e. the number of lithium ions gradually increases in the active material and the lithium diffusion coefficient decreases.
  • the lithium diffusion coefficient of Li 0.89 (Mn 0.25 Fe 0.75 )(PO 4 ) 0.96 is 2.784 ⁇ 10 -10 ⁇ 7.014 ⁇ 10 -9 cm 2 /s depending on charge/discharge conditions, and that of Li(Mn 0.25 Fe 0.75 )PO 4 is 3.187 ⁇ 10 -11 ⁇ 6.387 ⁇ 10 -10 cm 2 /s. From this, it is understood that Li 0.89 (Mn 0.25 Fe 0.75 )(PO 4 ) 0.96 is about 4.62 ⁇ 10.98 times better than stoichiometric Li(Mn 0.25 Fe 0.75 )PO 4 in lithium diffusion coefficient.
  • the lithium diffusion coefficient of Li 0.91 (Co 0.25 Fe 0.75 )(PO 4 ) 0.97 is 2.832 ⁇ 10 -10 ⁇ 6.497 ⁇ 10 -9 cm 2 /s depending on charge/discharge conditions, and that of Li(Co 0.25 Fe 0.75 )PO 4 is 3.122 ⁇ 10 -11 ⁇ 6.257 ⁇ 10 -10 cm 2 /s. From this, it is understood that Li 0.91 (Co 0.25 Fe 0.75 )(PO 4 ) 0.97 is about 5.29 ⁇ 10.38 times better than stoichiometric Li(Co 0.25 Fe 0.75 )PO 4 in lithium diffusion coefficient.
  • the lithium diffusion coefficient of Li 0.91 (Ni 0.26 Fe 0.74 )(PO 4 ) 0.97 is 2.491 ⁇ 10 -10 ⁇ 5.877 ⁇ 0 -9 cm 2 /s depending on charge/discharge conditions, and that of Li(Ni 0.25 Fe 0.75 )PO 4 is 2.989 ⁇ 10 -11 ⁇ 5.990 ⁇ 10 -10 cm 2 /s. From this, it is understood that Li 0.91 (Ni 0.26 Fe 0.74 )(PO 4 ) 0.97 is about 4.59 ⁇ 9.81 times better than stoichiometric Li(Ni 0.25 Fe 0.75 )PO 4 in lithium diffusion coefficient.
  • the lithium diffusion coefficient of Li 0.89 (Mn 0.33 Co 0.33 Ni 0.33 )(PO 4 ) 0.96 is 1.008 ⁇ 10 -9 ⁇ 9.635 ⁇ 10 -9 cm 2 /s depending on charge/discharge conditions, and that of Li(Mn 0.33 Co 0.33 Ni 0.33 )PO 4 is 3.675 ⁇ 10 -11 ⁇ 5.962 ⁇ 10 -10 cm 2 /s. From this, it is understood that Li 0.89 (Mn 0.33 Co 0.33 Ni 0.33 )(PO 4 ) 0.98 is about 12.02 ⁇ 27.43 times better than stoichiometric Li(Mn 0.33 Co 0.33 Ni 0.33 )PO 4 in lithium diffusion coefficient.
  • the lithium diffusion coefficient of Li 0.90 (Mn 0.25 Co 0.25 Ni 0.25 Fe 0.25 )(PO 4 ) 0.97 is 4.140 ⁇ 10 -10 ⁇ 8.415 ⁇ 10 -9 cm 2 /s depending on charge/discharge conditions, and that of Li(Mn 0.25 Co 0.25 Ni 0.25 Fe 0.25 )PO 4 is 2.998 ⁇ 10 -11 ⁇ 6.962 ⁇ 10 -10 cm 2 /s. From this, it is understood that Li 0.90 (Mn 0.25 Co 0.25 Ni 0.25 Fe 0.25 )(PO 4 ) 0.97 is about 8.39 ⁇ 13.81 times better than stoichiometric Li(Mn 0.33 Co 0.33 Ni 0.33 )PO 4 in lithium diffusion coefficient.
  • lithium diffusion coefficients confirms that if a lithium transition-metal phosphate runs short of anions, lithium diffusion coefficient increases by up to about 27 times, and that anion vacancies facilitates lithium diffusion.
  • Table 9 shows lithium ion diffusion coefficients measured with the GITT method on the anion-deficient lithium transition-metal phosphates synthesized in Examples 15, 16, and 17, where all of the measurements were conducted at a 40% state of charge (SOC).
  • Lithium ion diffusion coefficients of the lithium transition-metal phosphates synthesized in Examples 15, 16, and 17 Compound Lithium lon Diffusion Coefficient (cm 2 /s)
  • Example 15 Li 0.88 (Mg 0.07 Fe 0.93 )(PO 4 ) 0.96 2.315 ⁇ 10 -9
  • Example 16 Li 0.92 (Mg 0.10 Mn 0.90 )(PO 4 ) 0.97 2.697 ⁇ 10 -9
  • Example 17 Li 0.85 (Al 0.03 Mn 0.78 Fe 0.19 )(PO 4 ) 0.98 2.214 ⁇ 10 -9
  • Figure 22 shows the relationship between the molar ratio of phosphorus to the metal M (P/M) and lithium diffusion coefficient.
  • lithium diffusion coefficient was measured with the GITT method on the lithium (manganese cobalt nickel iron) phosphates synthesized in Examples 14, 18, 19, 20 and 21 and Comparative Examples 14 and 15, at 40% SOC.
  • lithium ion diffusion coefficient can be improved by controlling the molar ratio P/M to be less than 1. When 0.95 ⁇ P/M ⁇ 0.99, the lithium diffusion coefficient is better than when P/M is 1. A more preferable lithium diffusion coefficient is achieved if 0.96 ⁇ P/M ⁇ 0.98.
  • the lithium diffusion coefficient greatly changes, which is because anions generated in an excessive amount lead to partial collapse of the crystal structure. Since the collapse of the crystal structure deteriorates electrochemical activity, generating an excessive amount of anion vacancies is not desirable.
  • An electrode slurry which contained an anion-deficient lithium transition-metal phosphate, a conducting agent, and a binder at a weight ratio of 90:5:5 was prepared.
  • the conducting agent was a mixture of super-P ® (conductive carbon black produced by TIMCAL Graphite & Carbon, Inc., Switzerland) and vapor-grown carbon fiber (VGCF), wherein the two compounds were contained at the weight ratio of 1:1, and the binder was KF1100 ® (polyvinylidene fluoride produced by Kureha Chemical Ind. Co., Ltd., Japan).
  • the electrode slurry was applied onto a thin aluminium sheet at an application speed of 0.3 m/min and was dried at 90°C in the front room and 120°C in the rear room of an applicator to fabricate a cathode.
  • An electrolyte was synthesized by dissolving 1 mol of LiPF 6 in a solvent which was a mixture of ethylene carbonate (EC) and ethyl methyl carbonate (EMC) at a volume ratio of 1:2.
  • EC ethylene carbonate
  • EMC ethyl methyl carbonate
  • a lithium secondary battery of a coin cell type was fabricated. Charge and discharge were conducted at the constant 0.1C rate by using a Maccor series 4000 (Maccor Inc., Tulsa, Oklahoma, U.S.A.).
  • Figures 23, 24 , and 25 are the charge/discharge graphs of lithium secondary batteries adopting the anion-deficient lithium manganese iron phosphates synthesized in Examples 1, 2, and 3 as cathode-active materials.
  • the cutoff potential of discharge was set at 3.0 volt
  • the anion-deficient lithium manganese iron phosphates of the present invention showed a discharge capacity of 136 to 149mAh/g, which is higher than those of conventional lithium manganese iron phosphates. Further, the gap between the charge potential and the discharge potential was narrow in the compounds of the present invention.
  • Figure 26 compares the charge/discharge graphs of lithium secondary batteries which adopt the lithium manganese iron phosphates synthesized in Example 2 and Comparative Example 2 as cathode-active materials.
  • the discharge capacity of the anion-deficient lithium manganese iron phosphate of Example 2 is about 138mAh/g, which is greater than 129mAh/g achieved by the stoichiometric lithium manganese iron phosphate of Comparative Example 2.
  • An anion-deficient lithium transition-metal phosphate of the present invention can be used as an electrode-active material for secondary batteries, memory devices, and capacitors including hybrid capacitors (P-EDLC), and other electrochemical devices, preferably as a cathode-active material for secondary batteries.
  • P-EDLC hybrid capacitors

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Ceramic Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Structural Engineering (AREA)
  • Materials Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Sustainable Energy (AREA)
  • Sustainable Development (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Secondary Cells (AREA)
EP10733657A 2009-01-22 2010-01-21 Aktives elektrodenmaterial für anionenarme lithiumübergangsmetallphosphatverbindung, herstellungsverfahren dafür und elektrochemische vorrichtung damit Withdrawn EP2390948A2 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR1020090005540A KR100939647B1 (ko) 2009-01-22 2009-01-22 전극 활물질인 음이온 부족형 비화학양론 리튬 전이금속 다중산 화합물, 그 제조 방법 및 그를 이용한 전기화학 소자
PCT/KR2010/000401 WO2010085104A2 (ko) 2009-01-22 2010-01-21 전극 활물질인 음이온 부족형 리튬 전이금속 인산화합물, 그 제조방법, 및 그를 이용한 전기화학 소자

Publications (1)

Publication Number Publication Date
EP2390948A2 true EP2390948A2 (de) 2011-11-30

Family

ID=42082875

Family Applications (2)

Application Number Title Priority Date Filing Date
EP10151284A Withdrawn EP2211404A1 (de) 2009-01-22 2010-01-21 Ektrodenaktive aniondefizientes nicht-stoichiometrisches Lithium-Eisenphophat und ein Herstellungsverfahren dafür
EP10733657A Withdrawn EP2390948A2 (de) 2009-01-22 2010-01-21 Aktives elektrodenmaterial für anionenarme lithiumübergangsmetallphosphatverbindung, herstellungsverfahren dafür und elektrochemische vorrichtung damit

Family Applications Before (1)

Application Number Title Priority Date Filing Date
EP10151284A Withdrawn EP2211404A1 (de) 2009-01-22 2010-01-21 Ektrodenaktive aniondefizientes nicht-stoichiometrisches Lithium-Eisenphophat und ein Herstellungsverfahren dafür

Country Status (8)

Country Link
US (2) US7858233B2 (de)
EP (2) EP2211404A1 (de)
JP (2) JP4625536B2 (de)
KR (1) KR100939647B1 (de)
CN (2) CN102292855B (de)
CA (1) CA2750328C (de)
TW (2) TW201036235A (de)
WO (1) WO2010085104A2 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015023168A1 (ru) * 2013-11-06 2015-02-19 Частное Учреждение "Назарбаев Университет Рисеч Энд Инновэйшн Систэм" Водный литий-ионный аккумулятор

Families Citing this family (54)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI466370B (zh) 2008-01-17 2014-12-21 A123 Systems Inc 鋰離子電池的混合式金屬橄欖石電極材料
EP2277828B1 (de) * 2008-03-31 2018-08-08 Toda Kogyo Corp. Verfahren zur herstellung von lithiumeisenphosphatpulver, lithiumeisenphosphatpulver mit olivinstruktur, kathodenblech unter verwendung des lithiumeisenphosphatpulvers und sekundärbatterie mit nichtwässrigem lösungsmittel
US9178215B2 (en) 2009-08-25 2015-11-03 A123 Systems Llc Mixed metal olivine electrode materials for lithium ion batteries having improved specific capacity and energy density
US9660267B2 (en) 2009-09-18 2017-05-23 A123 Systems, LLC High power electrode materials
TWI496737B (zh) * 2009-09-18 2015-08-21 A123 Systems Llc 磷酸鐵及其製備方法
CN102893432B (zh) 2010-04-21 2016-01-13 株式会社Lg化学 碳包覆的具有橄榄石晶体结构的锂铁磷酸盐和使用所述锂铁磷酸盐的锂二次电池
CA2810132C (en) 2010-09-03 2015-03-17 Showa Denko K.K. Method for producing lithium metal phosphate
TW201221468A (en) * 2010-11-18 2012-06-01 Green Energy Electrode Inc Preparation method for lithium iron phosphate cathode material
CN102637854B (zh) * 2011-02-15 2014-06-25 北京宏福源科技有限公司 一种锂离子电池多阴离子正极材料的制备方法
JP2012204150A (ja) * 2011-03-25 2012-10-22 Sumitomo Osaka Cement Co Ltd 電極活物質の製造方法と電極活物質及び電極並びに電池
KR101210756B1 (ko) * 2011-05-02 2012-12-10 삼성코닝정밀소재 주식회사 리튬이온 이차전지용 양극 활물질의 제조방법, 이에 의해 제조된 양극 활물질 및 이것을 포함하는 리튬이온 이차전지
FR2978137A1 (fr) * 2011-07-21 2013-01-25 Saint Gobain Ct Recherches Produit fondu a base de lithium
JP5709136B2 (ja) * 2011-09-05 2015-04-30 太平洋セメント株式会社 リン酸鉄リチウムの製造法、及びリン酸鉄リチウム系正極活物質の製造法
CN102502560A (zh) * 2011-09-27 2012-06-20 中国电子科技集团公司第十八研究所 一种磷酸铁锂前驱体元素控制方法
CN102420322B (zh) * 2011-11-21 2013-11-20 湖南杉杉户田新材料有限公司 一种锂二次电池用多元复合正极材料及其制备方法
KR101345259B1 (ko) * 2011-12-20 2013-12-27 한화케미칼 주식회사 이중관식 열교환기를 사용한 전극 활물질의 제조
EP2796407B1 (de) * 2011-12-21 2016-12-21 Advanced Lithium Electrochemistry Co., Ltd. Anodenmaterial ohne sauerstoff und herstellungsverfahren dafür
JP5838934B2 (ja) * 2012-08-30 2016-01-06 株式会社デンソー 非水電解質二次電池用正極活物質の製造方法
JP5988095B2 (ja) * 2012-09-28 2016-09-07 住友金属鉱山株式会社 リチウム二次電池用正極活物質の前駆体とその製造方法、および該前駆体を用いたリチウム二次電池用正極活物質とその製造方法、並びに該正極活物質を用いたリチウム二次電池
US9876247B2 (en) 2012-11-15 2018-01-23 Corning Incorporated Solid ceramic electrolytes
KR101586556B1 (ko) 2013-01-10 2016-01-20 주식회사 엘지화학 탄소 코팅 리튬 인산철 나노분말 제조방법
KR101561377B1 (ko) 2013-01-10 2015-10-20 주식회사 엘지화학 리튬 인산철 나노분말 제조방법
KR101561373B1 (ko) 2013-01-10 2015-10-19 주식회사 엘지화학 리튬 인산철 나노분말 제조방법
FR3000956B1 (fr) * 2013-01-17 2017-12-08 Commissariat Energie Atomique Procede de synthese d'un compose lim1-x-y-znyqzfexpo4 et son utilisation comme materiau d'electrode pour accumulateur au lithium
EP2965371B1 (de) * 2013-03-08 2019-05-08 Umicore Olivinzusammensetzung mit verbessertem zellverhalten
CN103247800A (zh) * 2013-04-25 2013-08-14 西安理工大学 锂离子电池正极硅酸亚铁锂材料的制备方法
US10076737B2 (en) 2013-05-06 2018-09-18 Liang-Yuh Chen Method for preparing a material of a battery cell
EP2997611B1 (de) 2013-05-15 2026-04-22 QuantumScape Battery, Inc. Festkörperkatholyt oder -elektrolyt für eine batterie
CN105764846B (zh) * 2013-11-26 2019-01-15 Sk新技术株式会社 锂复合磷酸盐类化合物及其制备方法
JP6378422B2 (ja) 2014-08-13 2018-08-22 ユミコア 改善された電池性能を有するオリビン組成物
CN104183844B (zh) * 2014-08-21 2016-05-18 浙江大学 锂离子电池正极材料磷酸锰锂纳米颗粒的水热合成法
WO2016210371A1 (en) 2015-06-24 2016-12-29 Quantumscape Corporation Composite electrolytes
JP6128181B2 (ja) * 2015-09-30 2017-05-17 住友大阪セメント株式会社 リチウムイオン二次電池用電極材料、リチウムイオン二次電池用電極材料の製造方法、リチウムイオン二次電池用電極およびリチウムイオン二次電池
KR102765039B1 (ko) 2015-12-04 2025-02-11 퀀텀스케이프 배터리, 인코포레이티드 리튬, 인, 황 및 요오드를 포함하는 전해질 및 음극액 조성물, 전기화학적 장치를 위한 전해질 막, 및 이들 전해질 및 음극액을 제조하는 어닐링 방법(annealing method).
JP6064309B2 (ja) * 2016-02-18 2017-01-25 住友金属鉱山株式会社 リチウム二次電池用正極活物質の前駆体とその製造方法、および該前駆体を用いたリチウム二次電池用正極活物質とその製造方法、並びに該正極活物質を用いたリチウム二次電池
US11342630B2 (en) 2016-08-29 2022-05-24 Quantumscape Battery, Inc. Catholytes for solid state rechargeable batteries, battery architectures suitable for use with these catholytes, and methods of making and using the same
TWI821195B (zh) * 2017-07-19 2023-11-11 加拿大商納諾萬麥帝瑞爾公司 合成橄欖石型磷酸鋰金屬陰極材料的方法
JP7280722B2 (ja) * 2019-03-15 2023-05-24 積水化学工業株式会社 非水電解質二次電池用正極及びリチウムイオン二次電池
CN109920997B (zh) * 2019-03-20 2022-11-15 南通百川新材料有限公司 一种用于全固态电池的磷酸钴锂材料及其制作方法
US12199326B2 (en) * 2019-05-10 2025-01-14 The Regents Of The University Of California Fabrication processes for metal-supported proton conducting solid oxide electrochemical devices
CN113891851A (zh) * 2019-05-27 2022-01-04 公益财团法人相模中央化学研究所 钠过渡金属聚阴离子及其制造方法
US11121354B2 (en) 2019-06-28 2021-09-14 eJoule, Inc. System with power jet modules and method thereof
TWI785881B (zh) 2019-06-28 2022-12-01 美商壹久公司 具有輔助氣體流的處理系統與方法及所製成用於電池的材料
US11376559B2 (en) 2019-06-28 2022-07-05 eJoule, Inc. Processing system and method for producing a particulate material
US11673112B2 (en) 2020-06-28 2023-06-13 eJoule, Inc. System and process with assisted gas flow inside a reaction chamber
WO2022097400A1 (ja) * 2020-11-06 2022-05-12 株式会社Ｇｓユアサ 蓄電素子用正極活物質、蓄電素子用正極、蓄電素子及び蓄電装置
CN112993227A (zh) * 2021-02-23 2021-06-18 雅安锂盛新能企业管理中心(有限合伙) 长循环寿命磷酸铁锂复合材料、正极材料及其制备方法
CN115557482A (zh) * 2021-07-01 2023-01-03 惠州比亚迪电池有限公司 一种磷酸铁锂正极材料的制备方法及锂离子电池
JP7806353B2 (ja) * 2021-07-27 2026-01-27 中央化工機株式会社 振動処理装置及び当該装置による処理方法
JPWO2023127951A1 (de) * 2021-12-28 2023-07-06
US20230387404A1 (en) * 2022-05-25 2023-11-30 Rivian Ip Holdings, Llc Olivine-based cathode materials with improved conductivity
CN115072694A (zh) * 2022-06-28 2022-09-20 衢州华友钴新材料有限公司 磷酸铁锂正极材料及其制备方法以及锂离子电池
CN116779778B (zh) * 2023-08-11 2024-02-09 深圳海辰储能控制技术有限公司 正极极片及其制备方法、储能装置和用电装置
CN119153825B (zh) * 2024-11-18 2025-03-21 中创新航科技集团股份有限公司 二次电池和用电装置

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4749551B2 (ja) 1999-04-06 2011-08-17 ソニー株式会社 正極活物質及び非水電解質二次電池
WO2000060679A1 (fr) 1999-04-06 2000-10-12 Sony Corporation Procede de production de matiere active de plaque positive et procede de fabrication de cellules a electrolyte secondaires non aqueuses
US6815122B2 (en) 2002-03-06 2004-11-09 Valence Technology, Inc. Alkali transition metal phosphates and related electrode active materials
CN100448071C (zh) * 2003-03-18 2008-12-31 黄穗阳 锂电池正极材料及其制备方法
JP2005158673A (ja) * 2003-10-31 2005-06-16 Toyota Motor Corp 電極活物質およびその製造方法ならびに非水電解質二次電池
TWI279020B (en) * 2004-11-03 2007-04-11 Tatung Co Ltd Preparation of olivine LiFePO4 cathode materials for lithium batteries via a solution method
CN100377392C (zh) * 2004-12-21 2008-03-26 中国科学院物理研究所 用于二次锂电池的含氧空位的磷酸铁锂正极材料及其用途
DE102005012640B4 (de) * 2005-03-18 2015-02-05 Süd-Chemie Ip Gmbh & Co. Kg Kreisprozess zur nasschemischen Herstellung von Lithiummetallphosphaten
US7939201B2 (en) * 2005-08-08 2011-05-10 A123 Systems, Inc. Nanoscale ion storage materials including co-existing phases or solid solutions
US7524529B2 (en) 2005-09-09 2009-04-28 Aquire Energy Co., Ltd. Method for making a lithium mixed metal compound having an olivine structure
US7494744B2 (en) * 2006-03-08 2009-02-24 Changs-Ascending Enterprise Co. Cathode material for Li-ion battery applications
CN101212048A (zh) * 2006-12-30 2008-07-02 比亚迪股份有限公司 一种锂离子二次电池的正极材料及含有该正极材料的电池
KR20090005540A (ko) 2007-07-09 2009-01-14 엘지디스플레이 주식회사 액정표시장치
US8052897B2 (en) * 2008-02-29 2011-11-08 Byd Company Limited Composite compound with mixed crystalline structure
CN102187502B (zh) * 2008-10-22 2014-07-09 株式会社Lg化学 具有改善的电极效率和能量密度的正极活性材料

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2010085104A2 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015023168A1 (ru) * 2013-11-06 2015-02-19 Частное Учреждение "Назарбаев Университет Рисеч Энд Инновэйшн Систэм" Водный литий-ионный аккумулятор
US20150207180A1 (en) * 2013-11-06 2015-07-23 Nazarbayev University Research and Innovation System Aqueous lithium-ion battery
US10347947B2 (en) 2013-11-06 2019-07-09 Nazarbayev University Research and Innovation System Aqueous lithium-ion battery

Also Published As

Publication number Publication date
JP4625536B2 (ja) 2011-02-02
HK1144616A1 (en) 2011-02-25
JP5318969B2 (ja) 2013-10-16
US20100183924A1 (en) 2010-07-22
JP2010170997A (ja) 2010-08-05
CN101789507B (zh) 2013-08-14
CA2750328A1 (en) 2010-07-29
CA2750328C (en) 2014-03-18
JP2012516016A (ja) 2012-07-12
TW201032377A (en) 2010-09-01
TW201036235A (en) 2010-10-01
WO2010085104A2 (ko) 2010-07-29
US7858233B2 (en) 2010-12-28
WO2010085104A3 (ko) 2010-12-02
TWI383533B (zh) 2013-01-21
EP2211404A1 (de) 2010-07-28
US20120021288A1 (en) 2012-01-26
WO2010085104A9 (ko) 2010-10-14
KR100939647B1 (ko) 2010-02-03
CN102292855B (zh) 2014-01-22
CN101789507A (zh) 2010-07-28
CN102292855A (zh) 2011-12-21

Similar Documents

Publication Publication Date Title
EP2390948A2 (de) Aktives elektrodenmaterial für anionenarme lithiumübergangsmetallphosphatverbindung, herstellungsverfahren dafür und elektrochemische vorrichtung damit
CN101946346B (zh) 用于锂离子蓄电池的混合的金属橄榄石电极材料
CN100340018C (zh) 充电电池用锂过渡金属磷酸盐粉末
JP5268134B2 (ja) 正極活物質の製造方法およびそれを用いた非水電解質電池
KR101264459B1 (ko) 결정성 나노메트릭 ＬｉＦｅＰＯ₄
JP5463561B2 (ja) オリビン構造を有する化合物及びその製造方法、並びにオリビン構造を有する化合物を使用する正極活物質及び非水電解質電池
CN101610977B (zh) 合成电活性晶态纳米LiMnPO4粉末
EP2360117A2 (de) Lithiumeisenphosphat mit olivinstruktur und herstellungsverfahren dafür
JPWO2000060679A1 (ja) 正極活物質の製造方法及び非水電解質二次電池の製造方法
KR20200042868A (ko) 리튬이차전지용 니켈계 활물질 전구체, 그 제조방법, 이로부터 형성된 리튬이차전지용 니켈계 활물질 및 이를 포함하는 양극을 함유한 리튬이차전지
US20160380269A1 (en) High power electrode materials
AU2018204689B2 (en) High power electrode materials
KR20160083567A (ko) 리튬이온 이차전지용 양극 활물질, 그의 제조방법 및 이것을 포함하는 리튬이온 이차전지
US20170170479A1 (en) Cathode materials containing olivine structured nanocomposites
KR102299253B1 (ko) 양극 활물질, 이의 제조 방법, 및 이를 포함하는 리튬 이차 전지
EP2630685B1 (de) Verfahren zur herstellung einer hochspannungsnanokompositkathode (4,9v) für lithiumionenbatterien
KR100805910B1 (ko) 리튬 전지용 올리빈형 양극 활물질, 이의 제조 방법, 및이를 포함하는 리튬 전지
KR20100086413A (ko) 전극 활물질인 음이온 부족형 비화학양론 리튬 전이금속 다중산 화합물, 그 제조 방법 및 그를 이용한 전기화학 소자
KR101070174B1 (ko) 전극 활물질인 음이온 부족형 리튬 전이금속 인산화합물, 그 제조방법, 및 그를 이용한 전기화학 소자
KR101801334B1 (ko) 양극 활물질용 전구체의 제조방법, 그로부터 얻어진 올리빈형 양극 활물질, 및 이를 포함하는 리튬 이차전지
HK1164551A (en) Electrode active material for anion-deficient lithium transition metal phosphate compound, method of preparing same, and electrochemical device using same
LI et al. preparing the same
TW201307197A (zh) 用於製備奈米粒子鋰過渡金屬磷酸鹽之方法
JP2023047468A (ja) リチウムイオン二次電池用正極活物質複合体粒子
HK1144616B (en) Electrode active material for anion-deficient lithium transition metal phosphate compound, method of preparing same, and electrochemical device using same

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20110819

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK SM TR

DAX Request for extension of the european patent (deleted)
REG Reference to a national code

Ref country code: HK

Ref legal event code: DE

Ref document number: 1164551

Country of ref document: HK

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20160802

REG Reference to a national code

Ref country code: HK

Ref legal event code: WD

Ref document number: 1164551

Country of ref document: HK